fix: separate full month fund from prorated fund

Monthly cards show full month fund (e.g., 168h for 21 days).
Yearly summary table uses fund_to_date (prorated to today for
current month) so the +/- column is accurate mid-month.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/admin/pages/AttendanceBalances.tsx

@@ -275,7 +275,8 @@ export default function AttendanceBalances() {
     let totalWorked = 0
     let totalCovered = 0
     for (const monthData of Object.values(fundData.months)) {
-      totalFund += monthData.fund
+      // Use prorated fund (fund_to_date) for current month, full fund for past
+      totalFund += (monthData as any).fund_to_date ?? monthData.fund
       const us = monthData.users?.[userId]
       if (us) {
         totalWorked += us.worked